Ancient Blue Dragon

D&D 5.5e · gargantuan dragon, lawful evil

Challenge 23 (50000 XP)

STR
29 (+9)
DEX
10 (+0)
CON
27 (+8)
INT
18 (+4)
WIS
17 (+3)
CHA
25 (+7)

Defense

Armor Class 22 (natural armor)
Hit Points 481 (26d20+208)
Speed 40 ft., fly 80 ft., burrow 40 ft.

Proficiencies & Senses

Saving Throws Dex +7, Wis +10
Skills Perception +10, Stealth +7
Languages Common, Draconic
Blindsight 60 ft.
Passive Perception 20

Traits

Damage Immunities Lightning

Traits

Legendary Resistance

If the monster fails a saving throw, it can choose to succeed instead.

Actions

Multiattack

The monster makes three Rend attacks. It can replace one attack with a use of Spellcasting to cast Shatter (level 3 version).

Rend

Melee Weapon Attack: +16 to hit, reach 15 ft., one target. Hit: 2d10+9 slashing damage plus 2d8 lightning damage.

Lightning Breath

Dexterity Saving Throw: DC 23, each creature in a 120-foot-long, 10-foot-wide Line. Failure: 16d10 lightning damage. Success: Half damage.

Spellcasting

The monster casts one of the following spells, requiring no Material components and using Charisma as the spellcasting ability (spell save DC 22): At Will: Detect Magic, Invisibility, Mage Hand, Shatter (level 3 version). 1/Day Each: Scrying, Sending.

Reference Text

Ancient blue dragons are lawful evil dragons that dwell in coastal and desert regions. They are cunning and territorial, using their lightning breath and spellcasting to dominate their domains.